Apparatus for flowing wells by air lift



w. L. MARTIN Feb. 10, 1931.

APPARATUS FOR FIIJOWING WELLS BY AIR LIFT Filed Feb. 1, 1928 g0 INVENTORW/Yfi riL Mari/n ATTORN EY Patented Feb. 10, 1931 UNITED STATES PATENTOFFICE 'WILBERT L. MARTIN, OF TULSA, OKLAHOMA APPARAT'llS FOR FLOWINGWELLS BY AIR LIFT Application am February 1, 1928. Serial no, 251,036.

, maintaining a column of fluid above the level normally maintainable bythe rock pressure, and to provide a continuous flow of the oil byintroduction of gas under pressure into the tubing at variouselevations, whereby a fluid column is maintained by the natural pressureand stepped upwardly in continuous flow by the artificial pressure.

-In accomplishing these and other ob ects of the invention I haveprovided improved details of structure, the preferred forms of which areillustrated in the accompanying drawings, wherein: 1/

Fig. 1 is a perspective view of an 011 well equipped with my improvedapparatus, the

well and its casing being in central vertical section.

Fig. 2 is an enlarged detail perspective view of the apparatus s owingthe tubing in vertical section, part of the enclosed apparatus beingbroken away for better illustration.

Referring in detail to the drawings:

1 desi nates a well hole having a well pocket 2 in a strata of oilbearing sand 3, the

I well hole being lined with casing 4 supported upon the cap rock 5 bythe casin ishoe 6, the casing being cap ed and sealed y a caslng head 7Suspen ed within the casing is a well tubing 8 having the usual strainer9 at its lower end extending into the pocket 2, the upper end of thetubing extending through the casing head 7 and being provided with a Tfitting 10 with which the flow pipe 11 is connected. An inlet pipe 12for gas under pressure, which will be referred to as air, introducedinto the casing head whereby air is admitted to the casing to lift thefluid re- 'ceived in the tubing through the strainer for deliverythrough the pipe 11 to storage means (not shown).

Supported by and in the caslng 8 near the bottom of the well is a packer13 providing upper and lower chambers 14 and 15 in the so casing andsealing of! the natural rock pressure within the lower chamber toconserve said pressure and to render it efl'ective for lifting the fluidin the tubing, and also for preventing back pressure on the fluid byartificial pressure medium introduced into the i5 casing.

In the early stages of the flowing of wells natural rock pressure liftsthe column of fluid to a relatively high level in the tubing, from whichlevel the artificial pressure medium may pick it up and urge it to thetop of the well. In'order to assist the natural rock pressure tomaintain a fluid column at a desired level after the latter has becomepartially exhausted, I haveprovided for the introduction of air underpressure at a point adjacent the bottom of the tubing, means thereforcomprising a transverse, tubular inlet nipple 16 in the tubin havinginlet ports 17 in the walls of the tu ing, and a pipe 18 connected intosaid nipple extending downwardly in the tubing to a level in the pocket2 preferably slightly above the level of the oil sand, whereby air underpressure is conducted from the upper casing chamber for discharge intothe tubing below the level of the fluid maintained by the rock pressure.Screw-threaded on the lower end of the pipe 18 is a conical cap 19having a distributing chamber 20 and ducts 21 leading upwardly andangularly from the chamber for delivery into the interior of the tubing,whereby air under pressure passing from the easing into the pipe will bedischarged upwardly against the column of fluid in the tubing to assistthe 35 natural rock pressure in initially lifting the oil through thetubing. The cap member is provided with exterior grooves or channels 22,whereby fluid admitted to the tubing through the strainer portionthereofis permitted to pass the cap. 4

Positioned in the tubing above the transverse inletg ipple member 16 arenozzles 23 angularly directed upwardly toward the center of the tubing,having inlet ports 24 for admitting air under pressure from the casinginto the tubing; the inner ends 25 being restricted slightly to providestop flanges for retaining the back-check ball valves 27, which" seatdownwardly on seats 28 n'n the nozzle channels, for preventing returnflow of fluid from the tubing into the casing.

In practicing the invention, the apparatus being installed as described,air under pressure admitted to the casing moves simultaneously throughthe ports of the inclined inlet nozzles 23 and inlet nipple 16. Airentering through the ni ple is conducted into the cap adjacent the oilpocket and, being emitted therefrom, assists the natural rock pressurein raising the oil in the tubing to a level where it may be acted uponby the air entering the tubing through the nozzles 23 to lift the oilthrough the tubing to the upper end thereof,

31 from which it is discharged into the flow pipe and conducted tostorage. The natural rock pressure being retained beneath the packer is,therefore, permitted to act upon the oil in the pocket to lift the oilto the limit of its ability, and the air under pressure conducted by thedepending pipe into the lower end of the tubing picks up the oil at anylevel to which it has been raised by the rock pressure and elevates itfurther to a position where it may be acted upon by the primary pressureinflow.

ll hat I claim and desire to secure by Letters Patent is:

1" In combination with well. casing, a

an packer in the casing, tubing extending through the packer, a conduitin the tubing communicating with the casing above the packer andterminating in the tubing below the packer, a cap on the lower end ofthe conduit having a distributing chamber and ducts leading from saidchamber to communication with the casing below the packer, nipples inthe tubing communicating with the casing above the packer, and means fordelivering air under pressure to the casing above the packer. I

2. In combination with well casing, a packer in the casing, tubingextending through the packer, a conduit in the tubing communicating withthe casing above the packer and terminating in the tubing below thepacker, a cap on the lower end of the conduit having a distributingchamber, having ducts leading from said chamber to communication withthe casing below the packer and having exterior passageways for wellfluid, nipples in the tubing communieating with the casing above thepacker, and means for delivering air under pressure to the casing abovethe packer.

3. In combination with well casing, a packer in the casing, tubingextending through the packer, a conduit in the tubing having a la -headcommunicating with the casing above the packer and a body portionterminating in the tubing below the packer, a cap on the lower end ofthe conduit having a distributing chamber and ducts leading from saidchamber to communication with wearer the casing below the packer,nipples in the tubing communicating with the casing above the packer,and means for delivering air under pressure to the casing above thepacker.

In testimony whereof ll afix my signature.

WILBERT L. MARTIN.

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